From patchwork Thu Aug 12 07:50:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 12432769 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CD5EC4320E for ; Thu, 12 Aug 2021 07:50:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1A1360FC4 for ; Thu, 12 Aug 2021 07:50:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234829AbhHLHun (ORCPT ); Thu, 12 Aug 2021 03:50:43 -0400 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:51846 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232348AbhHLHun (ORCPT ); Thu, 12 Aug 2021 03:50:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1628754619; x=1660290619; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=OaHm0g4Pt7Dgnern0abkbViMMO5KfKOhJvpYT/SNmVk=; b=T6w6cI7mUrVUAeV3vlxhD7Wi4cm32p2C3b/6mbBecUY2h+6WNNbzLSS5 H/TPjiFQTwn852XFxAkLeHPZafNvO0oepesEdlT+9ANP9dkBeNlbE4U09 TRWRIUuAJalmck9oUxdF8zilw0poE1E2kiO+STBHtVG5ADMv1O6ZiZmtg KJpt1mu3wtzhJp4F+HXfUGjreZLJC615TGxpIxbBez7k7oqFib1D9CrQf zAMu7xApDglGPu0mDCxIqTYzhT0UZ+4kUmy+31XZJfRwdkJjBFocn8J8S mznrSdnpCjvrnd/WX+8lLaUokUOD21h+8vCF2e6GSvciD0h+wMy212ajc Q==; X-IronPort-AV: E=Sophos;i="5.84,315,1620662400"; d="scan'208";a="177596933" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 12 Aug 2021 15:50:19 +0800 IronPort-SDR: Ij36qF9yE8jXU460vT+rPgSIVA8s0cV7ZxtioXEBu+Z9fdaX/eYofklvUcgDK25TtJZXZ1Conw Im7F+j351ML7bQr0IvdeFLSYIcL15+D+PIjWmORWe5iBMITnA91CKEsgGZraafKO2KGuyycI2l c9UrZKo7vPUILzMjs5SJEQKZ5jj3chlIRMxKP/jZz1PJJ4vPF+lDVp4aoWAFRP0dS5EQykpmQj ZW0U010kGurSFjwc8gZ1lQLmqToQwrwzHGwRwuHBi7LmRR6VPYUC0IzMppKLs3SDC9gQAA+/mt zPIByNh2q6YINTG2IqU3BJI4 Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Aug 2021 00:25:47 -0700 IronPort-SDR: ZqKUMYfPgArYz2yrHzvCWLs/n/tInJNUysJkLhRAcIZa63y2kGmJNDyqZidldaCYCuN4ESY76J YW/Es8Ck5wkOgb7p6uWHHF7IMhhAdXI15035cGEo/6lSALjWN5H2D4EpSqlYjpXCjwUowG0TyX q4fdYDhH/B1qd1YoXrYLqO4l/csP/hm7x+xFbddpjYtKFFBqqdI8pYTash2odK90KZORDnH8wV F5+iq93cL0yEcpdkoSTNdwZc88XYcu4ylQISTXZtFDzZPXi1F4s+PLOWS8C2Q8BgBT6V8I2Gh+ pQU= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 12 Aug 2021 00:50:17 -0700 From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Subject: [PATCH v5 1/5] block: Add concurrent positioning ranges support Date: Thu, 12 Aug 2021 16:50:11 +0900 Message-Id: <20210812075015.1090959-2-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210812075015.1090959-1-damien.lemoal@wdc.com> References: <20210812075015.1090959-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The Concurrent Positioning Ranges VPD page (for SCSI) and Log (for ATA) contain parameters describing the number of sets of contiguous LBAs that can be served independently by a single LUN multi-actuator disk. This patch provides the blk_queue_set_cranges() function allowing a device driver to signal to the block layer that a disk has multiple actuators, each one serving a contiguous range of sectors. To describe the set of sector ranges representing the different actuators of a device, the data type struct blk_cranges is introduced. For a device with multiple actuators, a struct blk_cranges is attached to the device request queue by the disk_set_cranges() function. The function disk_alloc_cranges() is provided for drivers to allocate this structure. The blk_cranges structure contains kobjects (struct kobject) to register with sysfs the set of sector ranges defined by a device. On initial device scan, this registration is done from blk_register_queue() using the block layer internal function disk_register_cranges(). If a driver calls disk_set_cranges() for a registered queue, e.g. when a device is revalidated, disk_set_cranges() will execute disk_register_cranges() to update the queue sysfs attribute files. The sysfs file structure created starts from the cranges sub-directory and contains the start sector and number of sectors served by an actuator, with the information for each actuator grouped in one directory per actuator. E.g. for a dual actuator drive, we have: $ tree /sys/block/sdk/queue/cranges/ /sys/block/sdk/queue/cranges/ |-- 0 | |-- nr_sectors | `-- sector `-- 1 |-- nr_sectors `-- sector For a regular single actuator device, the cranges directory does not exist. Device revalidation may lead to changes to this structure and to the attribute values. When manipulated, the queue sysfs_lock and sysfs_dir_lock are held for atomicity, similarly to how the blk-mq and elevator sysfs queue sub-directories are protected. The code related to the management of cranges is added in the new file block/blk-cranges.c. Signed-off-by: Damien Le Moal --- block/Makefile | 2 +- block/blk-cranges.c | 310 +++++++++++++++++++++++++++++++++++++++++ block/blk-sysfs.c | 26 ++-- block/blk.h | 4 + include/linux/blkdev.h | 29 ++++ 5 files changed, 362 insertions(+), 9 deletions(-) create mode 100644 block/blk-cranges.c diff --git a/block/Makefile b/block/Makefile index 0d951adce796..7b8a2b969537 100644 --- a/block/Makefile +++ b/block/Makefile @@ -9,7 +9,7 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-sysfs.o \ blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \ blk-mq-sysfs.o blk-mq-cpumap.o blk-mq-sched.o ioctl.o \ genhd.o ioprio.o badblocks.o partitions/ blk-rq-qos.o \ - disk-events.o + disk-events.o blk-cranges.o obj-$(CONFIG_BOUNCE) += bounce.o obj-$(CONFIG_BLK_SCSI_REQUEST) += scsi_ioctl.o diff --git a/block/blk-cranges.c b/block/blk-cranges.c new file mode 100644 index 000000000000..9994301414ee --- /dev/null +++ b/block/blk-cranges.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Block device concurrent positioning ranges. + * + * Copyright (C) 2021 Western Digital Corporation or its Affiliates. + */ +#include +#include +#include +#include + +#include "blk.h" + +static ssize_t blk_crange_sector_show(struct blk_crange *cr, char *page) +{ + return sprintf(page, "%llu\n", cr->sector); +} + +static ssize_t blk_crange_nr_sectors_show(struct blk_crange *cr, char *page) +{ + return sprintf(page, "%llu\n", cr->nr_sectors); +} + +struct blk_crange_sysfs_entry { + struct attribute attr; + ssize_t (*show)(struct blk_crange *cr, char *page); +}; + +static struct blk_crange_sysfs_entry blk_crange_sector_entry = { + .attr = { .name = "sector", .mode = 0444 }, + .show = blk_crange_sector_show, +}; + +static struct blk_crange_sysfs_entry blk_crange_nr_sectors_entry = { + .attr = { .name = "nr_sectors", .mode = 0444 }, + .show = blk_crange_nr_sectors_show, +}; + +static struct attribute *blk_crange_attrs[] = { + &blk_crange_sector_entry.attr, + &blk_crange_nr_sectors_entry.attr, + NULL, +}; +ATTRIBUTE_GROUPS(blk_crange); + +static ssize_t blk_crange_sysfs_show(struct kobject *kobj, + struct attribute *attr, char *page) +{ + struct blk_crange_sysfs_entry *entry = + container_of(attr, struct blk_crange_sysfs_entry, attr); + struct blk_crange *cr = container_of(kobj, struct blk_crange, kobj); + ssize_t ret; + + mutex_lock(&cr->queue->sysfs_lock); + ret = entry->show(cr, page); + mutex_unlock(&cr->queue->sysfs_lock); + + return ret; +} + +static const struct sysfs_ops blk_crange_sysfs_ops = { + .show = blk_crange_sysfs_show, +}; + +/* + * crange entries are not freed individually, but alltogether with the + * struct blk_cranges and its array of range entries. since kobject_add() + * takes a reference on the parent struct blk_cranges kobj, the array of + * crange entries cannot be freed until kobject_del() is called for all entries. + * So we do not need to do anything here, but still need this nop release + * operation to avoid complaints from the kobject code. + */ +static void blk_crange_sysfs_nop_release(struct kobject *kobj) +{ +} + +static struct kobj_type blk_crange_ktype = { + .sysfs_ops = &blk_crange_sysfs_ops, + .default_groups = blk_crange_groups, + .release = blk_crange_sysfs_nop_release, +}; + +/* + * This will be executed only after all range entries are removed + * with kobject_del(), at which point, it is safe to free everything, + * including the array of range entries. + */ +static void blk_cranges_sysfs_release(struct kobject *kobj) +{ + struct blk_cranges *cranges = + container_of(kobj, struct blk_cranges, kobj); + + kfree(cranges); +} + +static struct kobj_type blk_cranges_ktype = { + .release = blk_cranges_sysfs_release, +}; + +/** + * disk_register_cranges - register with sysfs a set of concurrent ranges + * @disk: Target disk + * @new_cranges: New set of concurrent ranges + * + * Register with sysfs a set of concurrent ranges for @disk. If @new_cranges + * is not NULL, this set of concurrent ranges is registered and the + * old set specified by q->cranges is unregistered. Otherwise, q->cranges + * is registered if it is not already. + */ +int disk_register_cranges(struct gendisk *disk, struct blk_cranges *new_cranges) +{ + struct request_queue *q = disk->queue; + struct blk_cranges *cranges; + int i, ret; + + lockdep_assert_held(&q->sysfs_dir_lock); + lockdep_assert_held(&q->sysfs_lock); + + /* If a new range set is specified, unregister the old one */ + if (new_cranges) { + if (q->cranges) + disk_unregister_cranges(disk); + q->cranges = new_cranges; + } + + cranges = q->cranges; + if (!cranges) + return 0; + + /* + * At this point, cranges is the new set of sector ranges that needs + * to be registered with sysfs. + */ + WARN_ON(cranges->sysfs_registered); + ret = kobject_init_and_add(&cranges->kobj, &blk_cranges_ktype, + &q->kobj, "%s", "cranges"); + if (ret) { + q->cranges = NULL; + kfree(cranges); + return ret; + } + + for (i = 0; i < cranges->nr_ranges; i++) { + cranges->ranges[i].queue = q; + ret = kobject_init_and_add(&cranges->ranges[i].kobj, + &blk_crange_ktype, &cranges->kobj, + "%d", i); + if (ret) { + while (--i >= 0) + kobject_del(&cranges->ranges[i].kobj); + kobject_del(&cranges->kobj); + kobject_put(&cranges->kobj); + return ret; + } + } + + cranges->sysfs_registered = true; + + return 0; +} + +void disk_unregister_cranges(struct gendisk *disk) +{ + struct request_queue *q = disk->queue; + struct blk_cranges *cranges = q->cranges; + int i; + + lockdep_assert_held(&q->sysfs_dir_lock); + lockdep_assert_held(&q->sysfs_lock); + + if (!cranges) + return; + + if (cranges->sysfs_registered) { + for (i = 0; i < cranges->nr_ranges; i++) + kobject_del(&cranges->ranges[i].kobj); + kobject_del(&cranges->kobj); + kobject_put(&cranges->kobj); + } else { + kfree(cranges); + } + + q->cranges = NULL; +} + +static bool disk_check_ranges(struct gendisk *disk, struct blk_cranges *cr) +{ + sector_t capacity = get_capacity(disk); + sector_t min_sector = (sector_t)-1; + sector_t max_sector = 0; + int i; + + /* + * Sector ranges may overlap but should overall contain all sectors + * within the disk capacity. + */ + for (i = 0; i < cr->nr_ranges; i++) { + min_sector = min(min_sector, cr->ranges[i].sector); + max_sector = max(max_sector, cr->ranges[i].sector + + cr->ranges[i].nr_sectors); + } + + if (min_sector != 0 || max_sector < capacity) { + pr_warn("Invalid concurrent ranges: missing sectors\n"); + return false; + } + + if (max_sector > capacity) { + pr_warn("Invalid concurrent ranges: beyond capacity\n"); + return false; + } + + return true; +} + +static bool disk_cranges_changed(struct gendisk *disk, struct blk_cranges *new) +{ + struct blk_cranges *old = disk->queue->cranges; + int i; + + if (!old) + return true; + + if (old->nr_ranges != new->nr_ranges) + return true; + + for (i = 0; i < old->nr_ranges; i++) { + if (new->ranges[i].sector != old->ranges[i].sector || + new->ranges[i].nr_sectors != old->ranges[i].nr_sectors) + return true; + } + + return false; +} + +/** + * disk_alloc_cranges - Allocate a concurrent positioning range structure + * @disk: target disk + * @nr_ranges: Number of concurrent ranges + * + * Allocate a struct blk_cranges structure with @nr_ranges range descriptors. + */ +struct blk_cranges *disk_alloc_cranges(struct gendisk *disk, int nr_ranges) +{ + struct blk_cranges *cr; + + cr = kzalloc_node(struct_size(cr, ranges, nr_ranges), GFP_KERNEL, + disk->queue->node); + if (cr) + cr->nr_ranges = nr_ranges; + return cr; +} +EXPORT_SYMBOL_GPL(disk_alloc_cranges); + +/** + * disk_set_cranges - Set a disk concurrent positioning ranges + * @disk: target disk + * @cr: concurrent ranges structure + * + * Set the concurrant positioning ranges information of the request queue + * of @disk to @cr. If @cr is NULL and the concurrent ranges structure + * already set, if any, is cleared. If there are no differences between + * @cr and the concurrent ranges structure already set, @cr is freed. + */ +void disk_set_cranges(struct gendisk *disk, struct blk_cranges *cr) +{ + struct request_queue *q = disk->queue; + + if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { + kfree(cr); + cr = NULL; + } + + mutex_lock(&q->sysfs_dir_lock); + mutex_lock(&q->sysfs_lock); + + if (cr) { + if (!disk_check_ranges(disk, cr)) { + kfree(cr); + cr = NULL; + goto reg; + } + + if (!disk_cranges_changed(disk, cr)) { + kfree(cr); + goto unlock; + } + } + + /* + * This may be called for a registered queue. E.g. during a device + * revalidation. If that is the case, we need to unregister the old + * set of concurrent ranges and register the new set. If the queue + * is not registered, the device request queue registration will + * register the ranges, so only swap in the new set and free the + * old one. + */ +reg: + if (blk_queue_registered(q)) { + disk_register_cranges(disk, cr); + } else { + swap(q->cranges, cr); + kfree(cr); + } + +unlock: + mutex_unlock(&q->sysfs_lock); + mutex_unlock(&q->sysfs_dir_lock); +} +EXPORT_SYMBOL_GPL(disk_set_cranges); diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 1832587dce3a..be8e02356a26 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -897,16 +897,15 @@ int blk_register_queue(struct gendisk *disk) } mutex_lock(&q->sysfs_lock); + + ret = disk_register_cranges(disk, NULL); + if (ret) + goto put_dev; + if (q->elevator) { ret = elv_register_queue(q, false); - if (ret) { - mutex_unlock(&q->sysfs_lock); - mutex_unlock(&q->sysfs_dir_lock); - kobject_del(&q->kobj); - blk_trace_remove_sysfs(dev); - kobject_put(&dev->kobj); - return ret; - } + if (ret) + goto put_dev; } blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); @@ -937,6 +936,16 @@ int blk_register_queue(struct gendisk *disk) percpu_ref_switch_to_percpu(&q->q_usage_counter); } + return ret; + +put_dev: + disk_unregister_cranges(disk); + mutex_unlock(&q->sysfs_lock); + mutex_unlock(&q->sysfs_dir_lock); + kobject_del(&q->kobj); + blk_trace_remove_sysfs(dev); + kobject_put(&dev->kobj); + return ret; } EXPORT_SYMBOL_GPL(blk_register_queue); @@ -983,6 +992,7 @@ void blk_unregister_queue(struct gendisk *disk) mutex_lock(&q->sysfs_lock); if (q->elevator) elv_unregister_queue(q); + disk_unregister_cranges(disk); mutex_unlock(&q->sysfs_lock); mutex_unlock(&q->sysfs_dir_lock); diff --git a/block/blk.h b/block/blk.h index 56f33fbcde59..149cd5ef8eeb 100644 --- a/block/blk.h +++ b/block/blk.h @@ -367,4 +367,8 @@ extern struct device_attribute dev_attr_events; extern struct device_attribute dev_attr_events_async; extern struct device_attribute dev_attr_events_poll_msecs; +int disk_register_cranges(struct gendisk *disk, + struct blk_cranges *new_cranges); +void disk_unregister_cranges(struct gendisk *disk); + #endif /* BLK_INTERNAL_H */ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 07eef02325b4..476fc5104a95 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -377,6 +377,29 @@ static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev, #endif /* CONFIG_BLK_DEV_ZONED */ +/* + * Concurrent sector ranges: struct blk_crange describes range of + * contiguous sectors that can be served by independent resources on the + * device. The set of ranges defined in struct blk_cranges must overall + * include all sectors within the device capacity. + * For a device with multiple ranges, e.g. a single LUN multi-actuator HDD, + * requests targeting sectors in different ranges can be executed in parallel. + * A request can straddle a range boundary. + */ +struct blk_crange { + struct kobject kobj; + struct request_queue *queue; + sector_t sector; + sector_t nr_sectors; +}; + +struct blk_cranges { + struct kobject kobj; + bool sysfs_registered; + unsigned int nr_ranges; + struct blk_crange ranges[]; +}; + struct request_queue { struct request *last_merge; struct elevator_queue *elevator; @@ -567,6 +590,9 @@ struct request_queue { #define BLK_MAX_WRITE_HINTS 5 u64 write_hints[BLK_MAX_WRITE_HINTS]; + + /* Concurrent sector ranges */ + struct blk_cranges *cranges; }; /* Keep blk_queue_flag_name[] in sync with the definitions below */ @@ -1161,6 +1187,9 @@ extern void blk_queue_required_elevator_features(struct request_queue *q, extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q, struct device *dev); +struct blk_cranges *disk_alloc_cranges(struct gendisk *disk, int nr_ranges); +void disk_set_cranges(struct gendisk *disk, struct blk_cranges *cr); + /* * Number of physical segments as sent to the device. *